© 2026 Aqora Quantum S.A.S.

Terms Privacy Legal Notice

Electronics and Communications in Japan (Part II Electronics)

Quantum‐information detection from optical memory using photonic crystals

Hiroyuki Nihei, Atsushi Okamoto

Published Jul 19, 2004• 0 citations

Abstract

Abstract There is now great interest in optical memory using a three‐level atom embedded in photonic crystals, which can be used for quantum computing; however, quantum‐information detection from the optical memory has not been demonstrated. In this paper, first, considering the relative position of the photonic band gap (PBG) and two atomic levels split from the upper level of the atom used for the optical memory, we demonstrate that one of the split levels must be outside the PBG for quantum‐information detection. In this case, the quantum state of the atom can be changed by moving the other split level, where the quantum information is maintained or emitted for the cases in which the split level is inside or outside the PBG, respectively. The emitted quantum information can be measured as spontaneous emissions by a photon detector. Next, we propose two methods of moving the split level: one is realized by applying a direct current (DC) field to the atom and the other is realized by changing the intensity of the control laser field. Furthermore, by evaluating the intensities of the DC and the control laser fields, we find that the quantum information can be measured using the fields on the millielectronvolt order. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 87(8): 10–19, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/ecjb.10205

DOI: 10.1002/ecjb.10205

Related papers

Quantum optics in a photonic band gap material

Sajeev John

Summary form only given. Unlike semiconductors which facilitate the coherent propagation of electrons, photonic band gap (PBG) materials execute their novel functions through the coherent localization of photons. When a PBG material is doped with impurity atoms which have an electronic transition that lies within the gap, spontaneous emission of light from the atom is inhibited. Inside the gap, the photon forms a bound state to the atom. Outside the gap, radiative dynamics in the colored vacuum is highly nonMarkovian. I discuss the influence of these memory effects on laser action. When spontaneous emission is absent, the next order radiative effect (resonance dipole-dipole interaction between atoms) must be incorporated, leading to anomalous nonlinear optical effects which occur at a much lower threshold than in ordinary vacuum. I describe the collective switching of two-level atoms near a photonic band edge, by external laser field, from a passive stare to one exhibiting population inversion. This effect is forbidden in ordinary vacuum. Finally, I discuss the prospects for a phase sensitive, single (3-level) atom quantum memory device, onto which information may be written by an external laser pulse. By scattering polarized photons (flying qubit) this system may execute certain quantum logic operations.

Quantum Electronics and Laser Science Conference•May 12, 2000•0 citations

Coherent control of spontaneous emission near a photonic band edge

Mesfin Woldeyohannes, Sajeev John

We demonstrate the coherent control of spontaneous emission for a three-level atom located within a photonic band gap (PBG) material, with one resonant frequency near the edge of the PBG. Spontaneous emission from the three-level atom can be totally suppressed or strongly enhanced depending on the relative phase between the steady-state control laser coupling the two upper levels and the pump laser pulse used to create an excited state of the atom in the form of a coherent superposition of the two upper levels. Unlike the free-space case, the steady-state inversion of the atomic system is strongly dependent on the externally prescribed initial conditions. This non-zero steady-state population is achieved by virtue of the localization of light in the vicinity of the emitting atom. It is robust to decoherence effects provided that the Rabi frequency of the control laser field exceeds the rate of dephasing interactions. As a result, such a system may be relevant for a single-atom, phase-sensitive optical memory device on the atomic scale. The protected electric dipole within the PBG provides a basis for a qubit to encode information for quantum computations. A detailed literature survey on the nature, fabrication and applications of PBG materials is presented to provide context for this research.

Journal of Optics B Quantum and Semiclassical Optics•Feb 13, 2003•88 citations

Optical memory using photonic crystals without external driving lasers for quantum computation

Hiroyuki Nihei, Atsushi Okamoto

In real photonic band gap (PBG) materials, the PBG is highly anisotropic. In this paper, we propose an optical memory composed of a three-level atom embedded in the realistic anisotropic PBG structures without external driving lasers, which can be considered as essential components for a novel class of computation including an optical quantum computation.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Sep 5, 2002•0 citations

Ultralow-loss optical quantum information processing in photonic bandgap devices

Hiroyuki Nihei, Atsushi Okamoto

We have demonstrated the coherent control of photonic bandgap (PBG) devices composed of a three-level atom embedded in three-dimensional PBG structures, which enables us to strongly suppress the loss of quantum information not only during its storage but also during its processing. We find that this ultralow-loss optical quantum information processing can be realized by generating the upper atomic level splitting inside the PBG and by tuning one of the split levels to a dark line in the emission spectrum (zeros in the spectrum at certain values of the emitted photon frequency). Furthermore, we show that the coherent control may provide a basis for the universal quantum logic gate operation in quantum computing.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•May 4, 2007•1 citation

Coherent control of spontaneous emission near a photonic band edge: A qubit for quantum computation

Mesfin Woldeyohannes, Sajeev John

We demonstrate the coherent control of spontaneous emission for a three-level atom located within a photonic band-gap structure with one resonant frequency near the edge of the photonic band gap. Spontaneous emission from the three-level atom can be totally suppressed or strongly enhanced depending on the relative phase between the steady-state control laser coupling the two upper levels and the pump laser pulse used to create an excited state of the atom in the form of a coherent superposition of the two upper levels. Unlike the free-space case, the steady-state inversion of the atomic system is strongly dependent on the externally prescribed initial conditions. This nonzero steady-state population is achieved by virtue of the localization of light in the vicinity of the emitting atom. It is robust to decoherence effects provided that the Rabi frequency of the control laser field-atom interaction exceeds the rate of dephasing interactions. As a result, such a system may be relevant for a single-atom, phase-sensitive, optical memory device on the atomic scale. The protected electric dipole within the photonic band gap provides a basis for a qubit to encode information for quantum computations.

Physical Review A•Dec 1, 1999•143 citations

All-optical switching scheme using a three-level atomic system within photonic crystals

Hiroyuki Nihei, Atsushi Okamoto

We propose all-optical switching schemes using a single three-level atomic system placed within a 3D photonic crystal that exhibits a complete 3D photonic band gap. The optical schemes we propose can be classified into two types with respect to a physical process that causes the switching effect. One switching type is mediated by changing an atom-field coupling strength. The other switching type is mediated by controlling quantum interference. Furthermore, we consider conditions of realizing a wide range of signals, which contributes to an improvement of the Signal to Noise ratio. The phases and strengths of the external laser fields required for the all-optical switching are revealed. Next, we estimate their switching times. Using these results, we propose the fastest scheme for every configuration of the atomic system, which is important for realizing a high-speed optical memory or switching device on an atomic scale that can be used in novel optical integrated systems, such as quantum computers.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Oct 30, 2001•0 citations

Abstract There is now great interest in optical memory using a three‐level atom embedded in photonic crystals, which can be used for quantum computing; however, quantum‐information detection from the optical memory has not been demonstrated. In this paper, first, considering the relative position of the photonic band gap (PBG) and two atomic levels split from the upper level of the atom used for the optical memory, we demonstrate that one of the split levels must be outside the PBG for quantum‐information detection. In this case, the quantum state of the atom can be changed by moving the other split level, where the quantum information is maintained or emitted for the cases in which the split level is inside or outside the PBG, respectively. The emitted quantum information can be measured as spontaneous emissions by a photon detector. Next, we propose two methods of moving the split level: one is realized by applying a direct current (DC) field to the atom and the other is realized by changing the intensity of the control laser field. Furthermore, by evaluating the intensities of the DC and the control laser fields, we find that the quantum information can be measured using the fields on the millielectronvolt order. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 87(8): 10–19, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/ecjb.10205

Summary form only given. Unlike semiconductors which facilitate the coherent propagation of electrons, photonic band gap (PBG) materials execute their novel functions through the coherent localization of photons. When a PBG material is doped with impurity atoms which have an electronic transition that lies within the gap, spontaneous emission of light from the atom is inhibited. Inside the gap, the photon forms a bound state to the atom. Outside the gap, radiative dynamics in the colored vacuum is highly nonMarkovian. I discuss the influence of these memory effects on laser action. When spontaneous emission is absent, the next order radiative effect (resonance dipole-dipole interaction between atoms) must be incorporated, leading to anomalous nonlinear optical effects which occur at a much lower threshold than in ordinary vacuum. I describe the collective switching of two-level atoms near a photonic band edge, by external laser field, from a passive stare to one exhibiting population inversion. This effect is forbidden in ordinary vacuum. Finally, I discuss the prospects for a phase sensitive, single (3-level) atom quantum memory device, onto which information may be written by an external laser pulse. By scattering polarized photons (flying qubit) this system may execute certain quantum logic operations.

We demonstrate the coherent control of spontaneous emission for a three-level atom located within a photonic band gap (PBG) material, with one resonant frequency near the edge of the PBG. Spontaneous emission from the three-level atom can be totally suppressed or strongly enhanced depending on the relative phase between the steady-state control laser coupling the two upper levels and the pump laser pulse used to create an excited state of the atom in the form of a coherent superposition of the two upper levels. Unlike the free-space case, the steady-state inversion of the atomic system is strongly dependent on the externally prescribed initial conditions. This non-zero steady-state population is achieved by virtue of the localization of light in the vicinity of the emitting atom. It is robust to decoherence effects provided that the Rabi frequency of the control laser field exceeds the rate of dephasing interactions. As a result, such a system may be relevant for a single-atom, phase-sensitive optical memory device on the atomic scale. The protected electric dipole within the PBG provides a basis for a qubit to encode information for quantum computations. A detailed literature survey on the nature, fabrication and applications of PBG materials is presented to provide context for this research.

We have demonstrated the coherent control of photonic bandgap (PBG) devices composed of a three-level atom embedded in three-dimensional PBG structures, which enables us to strongly suppress the loss of quantum information not only during its storage but also during its processing. We find that this ultralow-loss optical quantum information processing can be realized by generating the upper atomic level splitting inside the PBG and by tuning one of the split levels to a dark line in the emission spectrum (zeros in the spectrum at certain values of the emitted photon frequency). Furthermore, we show that the coherent control may provide a basis for the universal quantum logic gate operation in quantum computing.

We demonstrate the coherent control of spontaneous emission for a three-level atom located within a photonic band-gap structure with one resonant frequency near the edge of the photonic band gap. Spontaneous emission from the three-level atom can be totally suppressed or strongly enhanced depending on the relative phase between the steady-state control laser coupling the two upper levels and the pump laser pulse used to create an excited state of the atom in the form of a coherent superposition of the two upper levels. Unlike the free-space case, the steady-state inversion of the atomic system is strongly dependent on the externally prescribed initial conditions. This nonzero steady-state population is achieved by virtue of the localization of light in the vicinity of the emitting atom. It is robust to decoherence effects provided that the Rabi frequency of the control laser field-atom interaction exceeds the rate of dephasing interactions. As a result, such a system may be relevant for a single-atom, phase-sensitive, optical memory device on the atomic scale. The protected electric dipole within the photonic band gap provides a basis for a qubit to encode information for quantum computations.

We propose all-optical switching schemes using a single three-level atomic system placed within a 3D photonic crystal that exhibits a complete 3D photonic band gap. The optical schemes we propose can be classified into two types with respect to a physical process that causes the switching effect. One switching type is mediated by changing an atom-field coupling strength. The other switching type is mediated by controlling quantum interference. Furthermore, we consider conditions of realizing a wide range of signals, which contributes to an improvement of the Signal to Noise ratio. The phases and strengths of the external laser fields required for the all-optical switching are revealed. Next, we estimate their switching times. Using these results, we propose the fastest scheme for every configuration of the atomic system, which is important for realizing a high-speed optical memory or switching device on an atomic scale that can be used in novel optical integrated systems, such as quantum computers.